Fulcrum adjuster



NOV. 1957 A. c. SAMPIETRO FULCRUM ADJUSTER 3 Sheets-Sheet 1 Filed Aug. 23, 1956 9, 1957 A. c. SAMPIETRO 2,813,521

FULCRUM ADJUSTER Filed Aug. 23, 1956 3 Sheets-Sheet 2 Nov. 19, 1957 r A. c. SAMPIETRO 2,813,521

FULCRUM ADJUSTER Filed Aug. 23, 1956 i 3 Sheets-Sheet s United States Patent FULCRUM ADJUSTER Achilles Charles Sampietro, Detroit, Mich., assignor to Thompson Products, Inc., Cleveland, Ohio, a corporation of Ohio Application August 23, 1956, Serial No. 605,835

14 Claims. (Cl. 123-40) contained and the cartridge units are supported in positioned openings in a reaction bar which supplies pressurized oil to the cartridge units. The cartridge units contain an expansible oil chamber which maintains a bearing portion of the unit in pivotal non-lash engagement with the rocker arm. The cartridge units are assembled by being dropped into the openings in the reaction bar and are fixed in place by a common clamping unit.

The invention further contemplates the provision of a side guide member providing a sliding thrust surface to assimilate the lateral reaction forces which are incident to a push rod operated rocker arm and which are especially present in improved designs wherein the push rod must be set at an angle to the rocker arm.

An object of the invention is to provide an improved valve lash-preventing bearing assembly which is in the form of a self-contained unit cartridge and can be interchangeably used and replaced and requires no adjustment for installation.

Another object of the invention is to provide a selfcontained valve lash-preventing cartridge unit wherein the auxiliary mounting elements are inexpensive and require no close manufacturing tolerances and utilize a minimum number of parts.

Another object of the invention is to provide an arrangement wherein lateral reaction forces on the rocker arm are assimilated permitting the use of a compact rocker arm and push rod assembly that is not limited as to theangle of engagement between the relative parts.

A still further object of the invention is to provide an improved valve gear assembly having improved, operating characteristics and being inexpensive to manufacture and assemble without sacrificing wearing life or efficiency of operation.

Other objects and advantages will become more apparent with the disclosure of the invention in the specification and claims and appended drawings, in which:

Figure 1 is a vertical sectional view taken through a valve gear assembly and illustrating the details of an embodiment of the present invention;

Figure 2 is a sectional view taken along line II-II of Figure 1;

Figure 3 is an enlarged perspective view illustrating another embediment of the invention;

Figure 4 is a vertical view showing an enlarged valve lash cartridge assembly of an alternate form; i

. by a coil compression valve spring 22 which seats against Figure .5 is a plan view, with parts removed, of a pair of valve operating assemblies mounted on an engine; and

Figure 6 is another plan view illustrating a more completely assembled valve gear mechanism embodying the features of the present invention.

;.The drawings and specification illustrate and disclose vpreferred embodiments of the invention as utilized in a specific arrangement with valve-in-head internal combustion engine. It is to be understood that although the inand in the embodiment to be described, a plurality of valves will be arranged in a row or in a bank along the engine head to be alternately opened and closed as the engine operates. The valve 8 is of the poppet type and .is slidably mounted in a valve guide 10 suitably secured in the engine head 12. The engine head is of the conventional type having the usual passageways and ports with the combustion chamber being shown at 14in communication with a passageway 16 for the intake or exhaust of gases and to the chamber 14. The head 18 of the valve is held against a seat 20 when in closed position a shoulder 24 in the engine head 12 and which forces upwardly against a spring retaining washer 26 secured to th valve stem 28 by securing member 30.

The valve is operated by a rocker arm 32 which is formed of a fabricated shaped metal and has a valve stem engaging surface 34 pressing against the upper end 36 of the valve stem. The rocker arm is pivoted by a push rod 38 which has a spherical upper end 40 engaging a concave hollow 42 in the end of the rocker arm opposite the valve stem. The push rod is shown extending angularly past the valve stem 28 at one side thereof and its lowerend is provided with an enlarged bearing surface 44 slidably 44 is engaged by the rotating cam 46 mounted on the cam shaft 48. In operation, a plurality of push rods are arranged along the row of valves, each operated by their individual cams to open and close the valve at the proper time of operation.

The rocker arm 32 obtains its pivotal support from a bearing member 50 which is an element of the bearing cartridge 52 to be described later in detail. The bearing member 50 has a lower spherically shaped bearing end 51 which rests in the hollow spherical bearing surface 54 of the rocker arm.

In the form shown in Figure 1, the bearing member 50 has an upper cylindrically shaped end 56 which is slidably mounted in a housing or bearing support member 58. The bearing support member 58 and the bearing 50 together comprises the bearing cartridge 52. Between the bearing support member 58 and the bearing 50 is formed an expansible oil chamber 60. This expansible oil chamber receives pressurized oil from the oil system of the engine and the oil urges downwardly on the bearing 50 pressing it against the rocker arm which holds the rocker arm in non-lash engagement with the valve stem 28 and the push rod 38. The bearing member 50 is slidably mounted in the cylindrical inner surface of the support member 58 and a coil compression spring 62 is located in the pressure chamber 60 to urge the members .50 and 58 toward extended position to maintain the 66-at its upper end. 'The retaining member 66 contains a ball check valve 68 which seats against an orifice 70 when the bearing and support member 58 are moving together to close the pressure chamber 60; thereby preventing the escape of oil. "ing apart; the check valve 68 drops away from the orifice *70'to' permit pressurized oil to enter the pressure cham- When the members aremovber 60.

The bearing support member 58 is substantially "cylin- 'drical-in shape-and contains the cylindrical opening at its lower end to admit the bearing 507 The upper end "is solid-and contains a' crossdrilled oil passageway 72 -communicating withthe orifice'70 fordiscarding' oil into the pressure chamber 60. The passageway 72 communi- -cates with a conduit '74'extending' through the reaction bar 76 and in" communication with the oil gallery of the engine to receive pressurized oil. An annular groove 73 -extends peripherally around'the support member 58 to distribute-the oil from the conduit 74 to--both ends of the passageway 72. The-conduit 74 leads alongthe entire -length of the reaction-bar and distributes oil to each of the cartridges 52 that are arranged along the reaction bar.

To receive the individual cartridges, the reaction bar contains laterally extendingopenings 78 as is' shown -in 'Figures 1 and 2.

*To'distribute-oil to the conduit 74 and to the reaction bar,-a fitting is threaded into the 'endofthe reaction bar and connects to an oil line 82 leading to the oil pressure gallery of the engine.

For receiving the individual bearing cartridges 52 in the reaction bar, as is shown in Figures 1' and 2, the

cartridges drop loosely into the lateral holes 78 and 79 which extendthrough the bar and face'the rocker arms.

The upper ends of the holes are enlarged as to form a shoulder 80 against which seats the upper enlarged flanged end 82 of the support member- 58. Thus, in assembly, the cartridge is dropped into the opening 78 M79 and i the upper end 82 prevents the cartridge from passing 7 completely through the reaction bar.

To hold the cartridges in place, a clamping yoke 84 is provided having cartridge-engaging tips 86 and'88 which push the 'car- "tridgesdown firmly into their individual holes 78" and 79. The yoke is held in place by a stud 90 threaded into -a-hole92 in the reaction bar and beingthreaded at'its "upperend to receive a nut-94.

a washer -96 havinga spherical lower surface-that seats -in the spherical recess-98 in the yoke so that the yoke can adjust its position to apply an equal-pressure to each "of the cartridges.

It will be apparent that ayokecould be-provided to engage plurality of'cartridges' of -avarying member and that this arrangement permits rapid and simple assembly of the cartridges and reaction bar. The

openings 78 and 79 may be drilled'forrelativelyloose -fit ofthe cartridge and, therefore-no close expensive manufacturing tolerances need be maintained. The cartridges can easily be assembled or changed and are easily interchangeable and replaceable with no requirements for adjustment'or matching of parts.

"that the cartridge receiving openings 78 and 79 in the reaction bar 76 extend at an angle to the 'axisiof the bar.

It is to benoted This angle bisects the angle between the valve stem 28 and the push rod 38 so that the resultant force between the push rod and valve stem acts at an angle extending .parallelto the axis of the bearing cartridge.

This, of course, reduces the side thrust on the bearing cartridge and increases its operational life, although certain side thrusts are readily assimilated by the cylindrical sliding engagement between the bearing member. 50 and the sup- Y port member 58.

An assembled group of valves is illustrated in'Figure '6 with the valves 8 and 9 being operated by the'ro'cker arms 32 and 33. The lash-preventing cartridges 52* and 53 are positionedtin the openings 78and 79 of thereactionbar" 76 and are held in position by the yoke'84.

- between the 'push rod and rocker arm and this arrangement may also be provided in the embodiment of Fig. 1. Lubrication may be supplied by providing individual lubricating heads and it also may be obtained by the amount of leakage which is derived from the oil in the pressure chamber 60 passing down between the cylindrical walls of the bearing member 58 and the support member 58.

In the embodiment of Fig. 3, the bearing support member 104 has straight cylindrical Walls with no flange at the'upper end' and seats in a cylindrical opening in reaction bar 112 butwhich is not shown.

the reaction bar 112. Thebearing support member 104 'is provided with an annular'oil groove 114 which is in communication with the conduit extending through the The reaction bar is also provided with an' annular oil channel'116 which'is directly'opposite the groove 114 to forman oil reservoir for supplying the pressure chamber withinthe cartridge. While there is no means provided to prevent ;the' cartridge from sliding down in the opening, the internal spring in the pressure chamber similar to the spring 62 shown'in Fig. 1 will urge the bearing support member upwardly. To positionthe bearing support member the yoke 118 is provided with a lower flattened surface which rests against the upper fiat surface 120 of the reaction bar 112 and also against the upper fiat surface 122 of the cartridge was to accurately position the upper face of the cartridge.

Figure 4 illustrates a modified form of cartridge with the bearing'member 124 having a lower spherical bearing surface 126 for engaging the rocker arm and having up- "wa'rdly' extending" cylindrical walls which receive a bearing support member in the shape of a piston to slide on the inner surface of the bearing member 124 rather than on the outer surface as is the case with the cartridges illustrated in Figs. 1, 2 and 3. The support member 128 hasa lower cylindrical piston end 130 which slidably The nutclamps against extends into the interior of the bearing member 124 to form the oil pressure chamber 132. The compression spring 134' rests in the lower hollow end of the bearing member 124 and presses upwardly against a checkvalve retaining member 135 holding a ball check valve 136.

'The ball check valve is free to move away from the orifice 138 to permit oil to enter into the pressure chamber 132 and will move against the orifice 138 to prevent oil from leaving the pressure chamber 132 when the members 124 and 128 move together to reduce the size of the expansible pressure chamber 132. The bearing carrying member 128 has a hollow cylindrical oil reservoir 148 in its upper end which is threaded at 142 to receive a closing plug 144.

The reservoir communicates with lateral passageways 146 and 148 which are aligned with the conduit 150 through the reaction bar 152. The bearing support membermaybe cylindrical in shape at its enlarged upperend '154' and is slid into the opening 156 in the reaction bar 152. The cartridge unit consists of the bearing member 124 and the upper bearing support member 128 and is fixed in place by an end 158 of. a clamping yoke similar to that used with the arrangement illustrated in Figure 3.

,As is illustrated in Figure 1, the push rod 38 passes in front of the valve stem 28 so that there is an angle be tween the' push rod. and the verticalplane passing'through the valve stem. As was previously mentioned, the angle of :the cartridge -52.is suchas to bisect the-angle between the vertical plane ofthe valve stem and the angle that the push rod makes with this vertical plane. Thus, because of the angle'iof engagement between thepush rodiand rocker arm, the forces between the push rod 38 and the rocker arm 32 are such as to tend to rotate the rocker arm about the axis of the bearing member 50 due to the resultant side thrust forces. To prevent this rotation and assimilate the side thrust, a side guide member 160 is provided as is illustrated in Figures 1, 3 and 5. The side guide member 160 has a vertical bearing surface 162 against which slides the side of the rocker arm 32. In Fig. 3 the rocker arm 106 is shown moved slightly away from the bearing thrust surface 162 of the side guide member 160 to illustrate the contact surfaces. It will also be seen from Fig. 3 that the angle between the push rod 108 and the rocker arm 106 causes a'side thrust which is assimilated by the side guide 160.

The side guide block 160 is supported on the bracket 164 which is mounted on the engine head 12. This bracket carries at its upper end the reaction bar 76 in Figure 1, and the reaction bar 112 in Figure 3. The side guide block carries a pair of pins 166 and 168 which are received in holes 170 and 172 for positioning the block. The block is provided with a threaded hole 171, as shown in Fig. 3, which receives a bolt 173 as shown in Fig. 1.

Separate side guides are provided for each of the rocker arms, as shown in Fig. 5. In this figure the side guide 160 asssimilates the lateral thrusts caused by the push rods on the rocker arm 32 and the side guide 174 assimilates the lateral thrusts on the rocker arm 33. The rocker arms are supported on the bearing members 50 which extend into the spherical sockets as shown at 54 and 55 of Fig. 5, to thereby permit rotation of the rocker arm about an axis passing through the center of the bearing member 50. This permits slight lateral movement of each end of the rocker arm during operation and also makes it unnecessary to obtain extremely accurate positioning of the side guide member 160.

Although the operation of the mechanism as a whole will be clear from the foregoing detailed description of the individual elements, a summary of operation will be helpful in understanding the overall objectives and advantages of the mechanism. In operation the push rod 38, which passes to one side of the valve stem 28, reciprocates to rock the rocker arm 32 pushing down on the valve stem 28 to open and close the valve 8. The side thrust caused by the angular engagement between the push rod 38 and the rocker arm 32 is assimilated by a side guide block 160, shown in Figures 1 and 3, and by block 174 provided for rocker arm 33 as shown in Fig. 5. The rocker arm 32 is held in non-lash engagement with the valve stem 28 and the push rod 38 by a back lash preventing cartridge 52. The cartridge consists of a bearing member 56 and a bearing support member 58. The bearing member is urged downwardly into a pivotal en gagement with the socket 54 of the rocker arm by the pressure within the pressure chamber 60. Oil is forced into the pressure chamber from the conduit 74 of the reaction bar and the oil passes through the passageway 72, the bearing support member 58 and through the orifice '70 past the check valve 68. The lash preventing cartridge 52 is held in place, as shown in Figure 1, by yoke member 84 held against the top of the cartridge by bolt 90. Each of the individual cartridges are mounted in openings in the reaction bar 76 as is shown in Fig. 6 and are prevented from passing through the openings 78 in the reaction bar by the flange 82 on the bearing support member engaging the shoulder 80 within the opening, as it is shown in Figures 1 and 2.

Thus it will be seen that I have provided a fulcrum support for a rocker arm which meets the objects and advantages hereinbefore set forth. The fulcrum support is provided in the form of an integral cartridge which is easily assembled by merely dropping into the opening of the reaction bar. The openings in the reaction bar are drilled without the necessity of observing close tolerances which decreases the cost of manufacture and assembly. The assembly of the units is quicklyaccomplished by merely dropping the cartridges in the various holes and placing the clamping nuts or yokes in place. This can be accomplished quickly and easily without the necessity of making adjustments to the mechanism and can be done by semi-skilled personnel during assembly and can be readily repaired in a similar manner by merely replacing or interchanging the cartridge unit.

The cartridge unit is positioned to permit free pivotal movement of the rocker arm and the side guide block cooperates with the cartridge unit to prevent lateral stresses on the related operating units. The entire assembly is formed of dependable units and is susceptible to continued high speed operation without experiencing excessive wear or requiring frequent or accurate adjustment.

I have, in the drawings and specification, presented a detailed disclosure of the preferred embodimentsof my invention, but it is to be understood that I do not intend to limit the invention to the specified forms disclosed but intend to cover all modifications, changes and alternative constructions and methods falling within the scope of the principles taught by my invention.

I claim as my invention:

1. In a valve gear arrangement for an engine having a plurality of spring loaded valves with rocker arm actuators for the individual valves, the valve gear including individual bearing members in pivotal engagement with the rocker arm actuators, bearing support members in sliding engagement with each of the bearing members and forming an enclosed oil pressure chamber therebetween for pressurized oil to react on a surface of the bearing member, an-da reaction bar having a plurality of bearing support member-receiving openings with a support member in each of said openings to be positioned in the proper operative relationship to the spring loaded valves an rocker arm actuators.

2. In a valve gear for an engine having individual rocker arm actuators for operating the spring loaded valves of the engine, a plurality of bearing members in pivotal engagement with the rocker arms and urging them into operative non-lash engagement with the valves, bearing supporting members in operative engagement with each of the bearing members and forming an expansible oil pressure chamber therebetween for the oil to react on a surface of the bearing member, a common reaction bar having a plurality of holding locations thereon for receiving the bearing supporting members to support the bearing members in operating position relative to the rocker arms, and a oil conduit supported by said reaction bar and in communication with each of said bearing supporting mem- .bers to supply oil to said oil pressure chambers.

3. A valve lash preventing mechanism comprising an engine having a plurality of spring-loaded valves with separate rocker arm actuators, a bearing member for each rocker arm urging the rocker arm into non-lash engagement with the valve, a bearing support member operatively connected to each of the bearing members and forming an expansible oil pressure chamber therebetween to permit pressurized engine oil to react on a surface of the hearing member, a common reaction bar for supporting said support members and the bearing members in operating engagement with the rocker arm, and an oil passageway communicating with each of the pressure chambers between the bearing members and bearing support members.

4. In a valve gear including a plurality of push rods, rocker arms actuated by the rod, and spring loaded valves actuated by the rocker arms, the improvement comprising a common reaction bar extending substantially parallel to the plurality of valves and having openings extending therethrough facing each rocker arm, a bearing member for each of said rocker arms in lash-preventing pivotal engagement with the rocker arms, a bearing support member for each bearing member and being in sliding engagement therewith forming an oil pressure chamber therebetween to cause the oil within the chamber to react on a surface'of the bearing member, said bearing support memreaction bar. to limit the position of the supporting mem- .bers therein so that the support members may be easily slid into the openings, and an oil pressure conduit in communication with each of the oil pressure chambers to operatively urge the bearing members against the rocker arm in non-lash engagement therewith.

5.:In. an internal combustion engine having a plurality ofspring loaded valves with rocker arms in actuating ensgagement therewith and providedwith push rods for operatingthe rocker arms, a combination comprising a reaction bar extending parallel to said plurality of valves and provided withtr-ansverse openings, a bearing member for pivotally supporting each of said rocker arms in pressing engagement therewith to urge the rocker arm in nondashoperational engagement with the valves, a plurality of .bearing supportmembersin said openings in the reaction member, said bearing support members being operatively connected to each of the bearing members and forming an expansible oil. pressure chamber therebetween to permit the pressurized oil to react on a surface of the bearing member, and a bridging clamping member engaging a plurality of. the bearing support members to fixedly retain them in the openings in the reaction member.

6. In a valve gear assembly for an internal combustion engine having a plurality of spring loaded valves with individual rocker arms for actuating each of the valves and push rods for actuating the rocker arms, the improvement comprising individual bearing members in engagement with each of the rocker arms to pivotally support them and urge them to non-lash engagement with the valves and push rods, a bearing support member for each of the bearings forming an expansible oil chamber therebetween. for-the pressurized oil therein to urge the bearing member toward the rocker arm, a reaction bar extending adjacent said rocker arms and having a plurality of openings receiving the bearing support members, shoulders ineach of the openings limiting the movement .ofthe bearing support members toward the rocker arms,

i. av clamping yoke bridging across adjacent bearing support members. to urge them into the openings in the reaction .bar, andmeans to hold the clamping yoke against the bearing support members.

7. A valve gearassembly for operating a plurality of spring loaded engine valves provided with individual rocker'arms and operating push rods, the assembly comprising individual bearing members for each of the rocker arms urging the-arms intolnon-lash engagement with the valves and push rods, the bearing members having an upper. cylindrical end, individual bearing support membershaving cylindrical openings slidably receiving the bearing members and forming an expansible oil pressure chambertherebetween, external grooves extending circumferentially around the bearing support members and cornmunicating with theoil pressure chamber'therein, check valves within the oil pressure chambers to prevent a .reverse of'flow of oil out of the chamber, compression spring meansbetween the bearing support members and bearingumembers urging the oil pressure chamber to reactionbarand in communication with each ofsaid groovesof the bearing support members to distribute pressurized oil to the oil pressure chambers.

'8. A valve'gear arrangement for an internal combus- "tion*'engine having a plurality of rocker arm-actuated 'sspring-loadedwalves and push rods'positicned to operate -the rocker- -arms,*' the.combination comprising a plurality of bearing membersxengaging the rocker: arms andmrging them toward the valves and push rods in non-lash engagement, support members in operative engagement with each of the bearing members forming an expansible oil pressure chambertherebetween whereby the oil pressure reacts against a surface of the bearing member, a reaction bar extending adjacent the rocker arms and having a plurality of lateral openings for receiving the bearing support members, means for securing the bearing support members within the openings of the reaction bar, annular oil chambers in each of the openings of the reaction bar for distributing the oil to the pressure chambers, a passageway through the bearing support members communicating between the oil pressure chamber and the annular chamber in the reaction bar, and an oil pressure conduit connected to distribute oil to said annular chambers.

9. A valve combination for an internal combustion engine comprising a poppet valve having a spring-loaded stem, a rocker arm for actuating the valve stem, a pivotal support for the rocker arm, a push rod for the rocker arm to cause operation of the valve, and a lateral bearing surface in sliding engagement with the lateral side of the rocker arm at a point spaced from its pivotal support to guide the arm in its pivotal movement and prevent lateral movement with respect to the push rod or valve stem.

10. A valve assembly for an internal combustion engine comprising a poppet valve with an actuating stem, a rocker arm in operative engagement with the poppet valve, a pivotal support for said rocker arm, a push rod for pivoting the rocker arm to operate the valve, and a sliding surface in engagement with the lateral side of the rocker arm adjacent the push rod and guiding the push rod in its pivotal movement to prevent lateral thrusts against the push rod or valve stem.

' ll. A valve assembly for an internal combustion engine including a spring-loaded poppet valve with an operating valve stem, a rocker arm in engagement with the valve stem to open and close the poppet valve, a push rod in engagement with the opposite end of the rocker arm and extending at an angle to the plane of motion of the rocker arm, and a guide surface positioned laterally of the rocker arm to guide it in its plane of motion and assimilating lateral reactive forces due to the action of the push rod and valve stem on the rocker arm.

' 12. A valve gear assembly for an internal combustion engine comprising a spring-loaded poppet valve with an operating stem, a rocker arm adapted to operatively engage the valve stem, a push rod engaging the rocker arm to operate the valve, a bearing member supporting the push rod.

13. In a valve gear assembly including a push rod, a rocker arm actuated by the rod, and a spring loaded engine valve including a stem actuated by the arm, the improvement of a reaction bar having an opening therethrough facing the rocker arm, a bearing cartridge for the rocker arm inserted into said opening and including a bearing member having a cylindrical exterior, and a carrying member for said bearing member located in the opening in the reaction bar and having a cylindrical interior to slidably receive the bearing member to form an expansible oil chamber therebetween, a clamping member secured to the reaction bar and holding the carrying member within the reaction bar, and an oil passageway communicating with. the pressure chamber within the bearingcartridge to urge the bearing member into nonlash bearing engagement with the rocker arm.

14. In a valve gear including a push rod, a rocker arm actuated by .the rod, and t a spring-loaded 1 engine 1 valve including a stem actuated by the arm, the improvement of a reaction bar having opening therein facing the rocker arm, a bearing cartridge positioned in the opening and including a bearing member with a cylindrically shaped hollow interior, and a piston member slidably mounted in said interior to form an oil pressure chamber therebetween, said piston being mounted in the opening in the reaction bar, a clamping member secured to the reaction bar and holding said piston in place therein, and an oil pressure passageway in communication with the pressure chamber between the piston and bearing member to urge the bearing member against the rocker arm.

No references cited. 

